Simulation Driven Innovation

Study of Failure in Center Pivot Assembly oTechniques and Correlating

to Recommend t

S.K. Khare AGM-Rolling Stock

Larsen & Toubro Limited 12/4, Mathura Road

Faridabad-121003 (HR, IN)

Keywords: Failure, Optimization, Non

It has been observed that there are frequent failures in center pivot of casnubservice. Normal service life of a wagon is 2years between two consecutive ROH (Routine Overhauling) but due to failure in centhese wagons are removed causing low productivity and high maintenStudy was done to find possible areas of failure of pivot assembly and it was concluded that the maximum no of failures were failure of center pivot top. Existing design of center pivot top was analyzed by using FEA techniques and a corStudy was further extended to find new and better design for the center pivot. Same boundary conditions were used and by varymaterial properties & geometry, optimal design was found.

Introduction Study was done to find possible areas of failure of pivot assembly and it was concluded that the maximum no of failures were due to failure of center pivot top.

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of Failure in Center Pivot Assembly of Casnub Bogie Using nd Correlating the Results with Actual. Further

to Recommend the Design Changes.

Amardeep Singh Asst. Manager

Larsen & Toubro Limited 12/4, Mathura Road

Faridabad-121003 (HR, IN)

Rajan RahejaAsst. Manager

Larsen & Toubro Limited12/4, Mathura Road

Faridabad-121003 (HR, IN)

Failure, Optimization, Non-linear, Center pivot top.

Abstract

It has been observed that there are frequent failures in center pivot of casnub bogie. This results in an early removal of wagon from service. Normal service life of a wagon is 2years between two consecutive ROH (Routine Overhauling) but due to failure in centhese wagons are removed causing low productivity and high maintenance cost. Study was done to find possible areas of failure of pivot assembly and it was concluded that the maximum no of failures were

Existing design of center pivot top was analyzed by using FEA techniques and a correlation was found with the actual. Study was further extended to find new and better design for the center pivot. Same boundary conditions were used and by varymaterial properties & geometry, optimal design was found.

Study was done to find possible areas of failure of pivot assembly and it was concluded that the maximum no of failures were due to failure of center pivot top.

f Casnub Bogie Using FEA Further Extending Study

Rajan Raheja Asst. Manager

Larsen & Toubro Limited Mathura Road

121003 (HR, IN)

bogie. This results in an early removal of wagon from service. Normal service life of a wagon is 2years between two consecutive ROH (Routine Overhauling) but due to failure in center pivot

Study was done to find possible areas of failure of pivot assembly and it was concluded that the maximum no of failures were due to

relation was found with the actual. Study was further extended to find new and better design for the center pivot. Same boundary conditions were used and by varying

Study was done to find possible areas of failure of pivot assembly and it was concluded that the maximum

Simulation Driven Innovation

Process Methodology (details with figures)

• Data collection: Data was collected from various rehabilitation units and different research institutes

It was found that majority of failures (about 95%) was due to cracking of center pivot top. The

location and direction of crack

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Process Methodology (details with figures)

collected from various rehabilitation units and different research institutes

It was found that majority of failures (about 95%) was due to cracking of center pivot top. The

location and direction of crack was studied.

collected from various rehabilitation units and different research institutes.

It was found that majority of failures (about 95%) was due to cracking of center pivot top. The

Simulation Driven Innovation

• 3D model of center pivot was

• Step file was created for transferring the geometry to Hypermesh.

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3D model of center pivot was made.

Step file was created for transferring the geometry to Hypermesh.

Simulation Driven Innovation

• FE model creation

� Import of STEP solid from CAD.

� Geometric cleanup (using Auto cleanup)

� Defining Rigids for defining constraints.

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Import of STEP solid from CAD.

Geometric cleanup (using Auto cleanup)

igids for defining constraints.

Simulation Driven Innovation

• Iterations with varying loading condition to simulate the actual breakage.

• Iterations were done by varying the Geometry of pivot top to get the

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with varying loading condition to simulate the actual breakage.

Iterations were done by varying the Geometry of pivot top to get the Optimization

Optimization profile.

Simulation Driven Innovation

Results & Discussions

� A basic correlation was found between the actual fracture and the simulation results. � These results were then used to further optimize the existing design of center pivot top.

Benefits Summary The results found can be extended to design new and impro Challenges

� Finding the actual loading and boundary conditions, because in actual working scenario there are numerous forces which are acting due to motion of the system.

� Finding the correlation between the actual crack formation Future Plans We will try to use the Multibody techniques to accrue the more accurate forces from the system and further use these forces to do a reliability study in the pivot assembly. Conclusions

� By using the simple concepts of FEA we were able to find an equivalent load which can be used for simulating the actual field failure.

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A basic correlation was found between the actual fracture and the simulation results. These results were then used to further optimize the existing design of center pivot top.

The results found can be extended to design new and improved designs of pivot top.

actual loading and boundary conditions, because in actual working scenario there are numerous forces which are acting due to motion of the system. Finding the correlation between the actual crack formation and the FEA simulation.

techniques to accrue the more accurate forces from the system and further use these forces to do a reliability study in the pivot assembly.

By using the simple concepts of FEA we were able to find an equivalent load which can be used for simulating the actual field failure.

A basic correlation was found between the actual fracture and the simulation results. These results were then used to further optimize the existing design of center pivot top.

ved designs of pivot top.

actual loading and boundary conditions, because in actual working scenario there are

FEA simulation.

techniques to accrue the more accurate forces from the system and further use these

By using the simple concepts of FEA we were able to find an equivalent load which can be used for